DNA-based vaccine
Source: By The Times of India
NEW DELHI: As the world collectively battles the Covid-19 pandemic, scientists are now looking towards developing a DNA vaccine which can train the human immune system to ward off the infection, before it even takes root. Referred to as third-generation vaccine, a DNA-based vaccine uses engineered DNA to induce a response against the virus.
According to the World Health Organisation, this "radical new approach" offers several advantages over traditional vaccines, which include "improved vaccine stability, the absence of any infectious agent and the relative ease of large-scale manufacture." The technology, still in its nascent stage, has been developing rapidly in recent times.
If approved, Gujarat-based pharmaceutical major, Zydus Cadila, will become the first DNA vaccine. According to official sources, Zydus Cadila is likely to apply for emergency use authorization for its Covid-19 vaccine ZyCoV-D in a few days. Apart from adults, data is also being collected on if the vaccine can be administered to children belonging to the age group of 12 to 18 years.
There are presently various concerns of safety around rollout of new vaccines -- ranging from effect on immune system response to logistics and even public apprehension to certain vaccines.
The ZyCoV-D can be stored at two to four degree Celsius and will be a three-dose vaccine which will be administered intradermally. Furthermore, due to no requirement of cold chains, transportation to remotest parts of the country will also be made easy. At a time like this, many companies are stepping forward to help drive down the caseloads in the countries.
J&J vaccine technology previously tried out on HIV
J&J is developing vaccines using technologies that were previously tried out on HIV (human immunodeficiency virus). It is currently carrying out two human efficacy trials for its HIV vaccine candidate. Initial results from one of the vaccine are expected to be released by the end of this year
What's interesting to note here is that while the human immune system doesn't self-cure HIV, it is quite capable of self-curing Covid-19. The vaccine candidate is currently being trialed in 2,600 women in sub-Saharan Africa as well.
It's also being tested in around 3,800 men who have intercourse with men and transgender individuals across the US, South America and Europe in the Mosaico trial.
J&J vaccine uses similar adenovirus technology to its Covid-19 vaccine, a genetically modified cold virus delivers genetic cargo carrying instructions for the host to develop "mosaic immunogens". These molecules are capable of inducing an immune response to a wide variety of HIV strains.
